Windows users contemplating the cost of upgrading to Vista may need a fatter wallet than they thought. Besides shelling out for faster hardware, users should expect to pay for Vista upgrades for many of their favorite Windows software.

Rather than releasing free patches to update existing versions, leading vendors such as Adobe Systems, Symantec, and Intuit are choosing to add Vista compatibility only to new releases or still-in-development future products. Most of these new versions will add significant features along with Vista compatibility. And, vendors will argue, if Vista compatibility is a new feature, what's unfair about packaging a new feature only in new versions of their software, rather than going back and patching aging versions nearing the end of their product life cycle?